Question

    It’s a real case of fish out of water. Blennies (鲇鱼) in the South Pacific Ocean are gradually relocating to land to escape their predators (捕食者), in an example of evolution in action.

Fish first began crawling onto dry land about 400 million years ago, kicking off an evolutionary chain of events that led to humans. But their reasons for exiting the sea have been uncertain.

To look for clues, Terry Ord at the University of New South Wales in Australia has been studying several species of blennies at Rarotonga, the largest of the Cook Islands.

At low tide, blennies are commonly found swimming in rock pools around the edges of the island. But when high tide moves in, they climb up to dry land and move around the rocks until the tide retreats.

The researchers found that this is most likely to avoid predators that swim in with the rising tide – mainly bigger fish like lionfish.

To test what would happen if blennies did not have an escape plan, they made blenny models and sank them in the sea. The mimics ended up with wounds, bite marks and chunks-missing.

Of course, there are still dangers for blennies on land, like the occasional bird attack, but the predation risk on land is a third that of underwater.

What’s more, moving onto land has additional benefits for blennies. Holes in the rocks provide sheltered nests for laying eggs, and they can maintain their diet of bacteria.

In fact, several species of blenny fish at Rarotonga have already made the full transition to land-dwelling (陆生的) species. They continue to breathe with their gills, but have developed stronger tail fins and jump from rock to rock.

Ord believes that many evolutionary processes have been driven by the need to escape predators. “It is often assumed that animals move homes to find new sources of food, but in many cases, escaping predators is a stronger motivation.” he says.

1.Why do blennies climb to dry land when high tide comes?

A. To acquire better health.    B. To search for more food.

C. To seek safer living conditions.    D. To adapt to a new environment.

2.What does the underlined part “The mimics” in Paragraph 6 refer to?

A. The rocks in the water.    B. The predators of blennies.

C. The researchers of blennies.    D. The models of blennies.

3.What can be concluded from the last paragraph?

A. Ord’s research opens a new view.

B. Ord wonders why animals move homes.

C. Ord shows us the benefits of blennies’ evolution.

D. Ord has discovered how fish have become land dwellers.

4.Which of the following could be the best title for the text?

A. Blennies’ Living Habits

B. Why Blennies Choose to Live on Land

C. Blennies’ Evolutionary Process

D. How Blennies Escape from their Predators

Answer

1. C

2. D

3. A

4. B

【解析】

这是一篇说明文。短文主要介绍了鲇鱼离开海洋，迁移到陆地的原因。

1.细节理解题。由第五段“The researchers found that this is most likely to avoid predators that swim in with the rising tide – mainly bigger fish like lionfish.”可知，研究人员发现，这很可能是为了躲避那些随着潮水而来的捕食者——主要是像狮子鱼这样的大鱼。所以为什么鲇鱼在涨潮时爬到陆地上的原因是因为他们寻求更安全的生活条件。故C选项正确。

2.推理判断题。由第六段“To test what would happen if blennies did not have an escape plan, they made blenny models and sank them in the sea. The mimics ended up with wounds, bite marks and chunks-missing.”可知，为了测试如果鲇鱼模型没有逃生计划会发生什么，他们制作了鲇鱼模型，并把它们沉到海里。这些鲇鱼模型最后留下了伤口、咬痕和大块肉不见了。所以判断出第6段划线部分“The mimics”指的是鲇鱼的模型。故D选项正确。

3.推理判断题。由最后段“It is often assumed that animals move homes to find new sources of food, but in many cases, escaping predators is a stronger motivation.”可知，人们通常认为动物搬家是为了寻找新的食物来源，但在很多情况下，逃离捕食者是更大的动机。所以奥德的观点与人们认为动物搬家是为了寻找新的食物来源不同，他认为逃离捕食者是它们搬家的更大的动机。这样的理论为人们认识动物搬家研究开辟了一个新的视角。所以从最后一段可以得出结论是奥德的研究开辟了一个新的视野。故A选项正确。

4.标题归纳题。由第一段“It’s a real case of fish out of water. Blennies (鲇鱼) in the South Pacific Ocean are gradually relocating to land to escape their predators (捕食者), in an example of evolution in action.”可知，南太平洋的鲇鱼正逐渐迁移到陆地上，以躲避捕食者，这是进化的一个例子。以及下文主澳大利亚新南威尔士大学的特里·奥德的对这种现象的研究过程，研究的结论。都是围绕着为什么“为什么鲇鱼选择住在陆地上”而展开的。故短文最佳的标题为“为什么鲇鱼选择住在陆地上”。故B选项正确。